The present invention relates to the sensing changes in tissues associated with a spinal level. The invention may be particularly useful in the assessment of tissue density as it relates to the intradiscal environment. Herniation of disc material or other bulges may lead to patient pain and discomfort. Being able to detect the onset of these conditions may allow early medical intervention to treat the condition, stop its advance or slow the progression. However, it is currently difficult to monitor the condition of the anatomic structures adjacent a spinal segment. Thus, there is a need for a device and system that is able to monitor the spinal segment environment and sense changes that are indicators of potential problems. Early detection of an impending problem provides the surgeon with the ability to identify and treat the affected tissue.
Therefore, there remains a need for improved instrumentation and methods for measuring tissue density and changes in tissue density associated with a spinal segment.